/* ** $Id: lstate.c,v 2.36.1.2 2008/01/03 15:20:39 roberto Exp $ ** Global State ** See Copyright Notice in lua.h */ #include <stddef.h> #define lstate_c #define LUA_CORE #include "lua.h" #include "ldebug.h" #include "ldo.h" #include "lfunc.h" #include "lgc.h" #include "llex.h" #include "lmem.h" #include "lstate.h" #include "lstring.h" #include "ltable.h" #include "ltm.h" #define state_size(x) (sizeof(x) + LUAI_EXTRASPACE) #define fromstate(l) (cast(lu_byte *, (l)) - LUAI_EXTRASPACE) #define tostate(l) (cast(lua_State *, cast(lu_byte *, l) + LUAI_EXTRASPACE)) /* ** Main thread combines a thread state and the global state */ typedef struct LG { lua_State l; global_State g; } LG; static void stack_init (lua_State *L1, lua_State *L) { /* initialize CallInfo array */ L1->base_ci = luaM_newvector(L, BASIC_CI_SIZE, CallInfo); L1->ci = L1->base_ci; L1->size_ci = BASIC_CI_SIZE; L1->end_ci = L1->base_ci + L1->size_ci - 1; /* initialize stack array */ L1->stack = luaM_newvector(L, BASIC_STACK_SIZE + EXTRA_STACK, TValue); L1->stacksize = BASIC_STACK_SIZE + EXTRA_STACK; L1->top = L1->stack; L1->stack_last = L1->stack+(L1->stacksize - EXTRA_STACK)-1; /* initialize first ci */ L1->ci->func = L1->top; setnilvalue(L1->top++); /* `function' entry for this `ci' */ L1->base = L1->ci->base = L1->top; L1->ci->top = L1->top + LUA_MINSTACK; } static void freestack (lua_State *L, lua_State *L1) { luaM_freearray(L, L1->base_ci, L1->size_ci, CallInfo); luaM_freearray(L, L1->stack, L1->stacksize, TValue); } /* ** open parts that may cause memory-allocation errors */ static void f_luaopen (lua_State *L, void *ud) { global_State *g = G(L); UNUSED(ud); stack_init(L, L); /* init stack */ sethvalue(L, gt(L), luaH_new(L, 0, 2)); /* table of globals */ sethvalue(L, registry(L), luaH_new(L, 0, 2)); /* registry */ luaS_resize(L, MINSTRTABSIZE); /* initial size of string table */ luaT_init(L); luaX_init(L); luaS_fix(luaS_newliteral(L, MEMERRMSG)); g->GCthreshold = 4*g->totalbytes; } static void preinit_state (lua_State *L, global_State *g) { G(L) = g; L->stack = NULL; L->stacksize = 0; L->errorJmp = NULL; L->hook = NULL; L->hookmask = 0; L->basehookcount = 0; L->allowhook = 1; resethookcount(L); L->openupval = NULL; L->size_ci = 0; L->nCcalls = L->baseCcalls = 0; L->status = 0; L->base_ci = L->ci = NULL; L->savedpc = NULL; L->errfunc = 0; setnilvalue(gt(L)); } static void close_state (lua_State *L) { global_State *g = G(L); luaF_close(L, L->stack); /* close all upvalues for this thread */ luaC_freeall(L); /* collect all objects */ lua_assert(g->rootgc == obj2gco(L)); lua_assert(g->strt.nuse == 0); luaM_freearray(L, G(L)->strt.hash, G(L)->strt.size, TString *); luaZ_freebuffer(L, &g->buff); freestack(L, L); lua_assert(g->totalbytes == sizeof(LG)); (*g->frealloc)(g->ud, fromstate(L), state_size(LG), 0); } lua_State *luaE_newthread (lua_State *L) { lua_State *L1 = tostate(luaM_malloc(L, state_size(lua_State))); luaC_link(L, obj2gco(L1), LUA_TTHREAD); preinit_state(L1, G(L)); stack_init(L1, L); /* init stack */ setobj2n(L, gt(L1), gt(L)); /* share table of globals */ L1->hookmask = L->hookmask; L1->basehookcount = L->basehookcount; L1->hook = L->hook; resethookcount(L1); lua_assert(iswhite(obj2gco(L1))); return L1; } void luaE_freethread (lua_State *L, lua_State *L1) { luaF_close(L1, L1->stack); /* close all upvalues for this thread */ lua_assert(L1->openupval == NULL); luai_userstatefree(L1); freestack(L, L1); luaM_freemem(L, fromstate(L1), state_size(lua_State)); } LUA_API lua_State *lua_newstate (lua_Alloc f, void *ud) { int i; lua_State *L; global_State *g; void *l = (*f)(ud, NULL, 0, state_size(LG)); if (l == NULL) return NULL; L = tostate(l); g = &((LG *)L)->g; L->next = NULL; L->tt = LUA_TTHREAD; g->currentwhite = bit2mask(WHITE0BIT, FIXEDBIT); L->marked = luaC_white(g); set2bits(L->marked, FIXEDBIT, SFIXEDBIT); preinit_state(L, g); g->frealloc = f; g->ud = ud; g->mainthread = L; g->uvhead.u.l.prev = &g->uvhead; g->uvhead.u.l.next = &g->uvhead; g->GCthreshold = 0; /* mark it as unfinished state */ g->strt.size = 0; g->strt.nuse = 0; g->strt.hash = NULL; setnilvalue(registry(L)); luaZ_initbuffer(L, &g->buff); g->panic = NULL; g->gcstate = GCSpause; g->rootgc = obj2gco(L); g->sweepstrgc = 0; g->sweepgc = &g->rootgc; g->gray = NULL; g->grayagain = NULL; g->weak = NULL; g->tmudata = NULL; g->totalbytes = sizeof(LG); g->gcpause = LUAI_GCPAUSE; g->gcstepmul = LUAI_GCMUL; g->gcdept = 0; for (i=0; i<NUM_TAGS; i++) g->mt[i] = NULL; if (luaD_rawrunprotected(L, f_luaopen, NULL) != 0) { /* memory allocation error: free partial state */ close_state(L); L = NULL; } else luai_userstateopen(L); return L; } static void callallgcTM (lua_State *L, void *ud) { UNUSED(ud); luaC_callGCTM(L); /* call GC metamethods for all udata */ } LUA_API void lua_close (lua_State *L) { L = G(L)->mainthread; /* only the main thread can be closed */ lua_lock(L); luaF_close(L, L->stack); /* close all upvalues for this thread */ luaC_separateudata(L, 1); /* separate udata that have GC metamethods */ L->errfunc = 0; /* no error function during GC metamethods */ do { /* repeat until no more errors */ L->ci = L->base_ci; L->base = L->top = L->ci->base; L->nCcalls = L->baseCcalls = 0; } while (luaD_rawrunprotected(L, callallgcTM, NULL) != 0); lua_assert(G(L)->tmudata == NULL); luai_userstateclose(L); close_state(L); }